Based on the relationships between Bi3+ energy levels and environmental factor he in phosphors established before, positions of A band of Bi3+ in ZnWO4 and CdWO4 are predicted to lie in near ultraviolet region. ZnWO4:Bi3+ and CdWO4:Bi3+ were prepared via a precipitation method. By examining their photoluminescence, it was confirmed that Bi3+ 1S0-3P1 transition are located around 340 and 350 nm, matching well with predicted results, 357 nm and 377 nm, respectively. The emission spectra indicate that they can be effectively excited by 340 and 350 nm ultraviolet light, exhibiting a satisfactory green performance (560 and 537 nm), according with ultraviolet chip.

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